Discharge mechanism for a walking beam furnace

ABSTRACT

A discharge mechanism is provided for a furnace having means to convey work therethrough wherein the work is removed from the furnace by contact with a supporting member having an inclined plane. An example of such a furnace is a walking beam furnace wherein the end portion of the stationary rails of the walking beam furnace is inclined downwardly and a vertically moving member is provided which contacts the work and causes it to move down the incline through the force of gravity.

a United States Patent Enk [4 1 Sept. 26, 1972 1 1 DISCHARGE MECHANISM FOR A WALKING BEAM FURNACE [72] Inventor: Albert T. Enk, Toledo, Ohio [73] Assignee: Midland-Ross Corporation, Toledo,

Ohio

[22] Filed: Dec. 17, 1970 [21] Appl. No.: 99,068

[52] US. Cl. ..263/6 A [51] lnt. Cl ..F27d 3/00 [58] Field of Search ..263/6 R, 6 A

[56] References Cited UNITED STATES PATENTS 1,871,501 8/1932 De Coriolis ..263/6 A FOREIGN PATENTS OR APPLlCATlONS 1,086,721 8/1960 Germany ..263/6 A 1/1968 Germany ..263/6 R 844,160 7/1952 Germany ..263/6 A 1,143,841 2/1963 Germany ..263/6 A Primary Examiner-Charles J. Myhre Atlomey-Peter Vrahotes and Harold F. Mensing 5 7 ABSTRACT A discharge mechanism is provided for a furnace having means to convey work therethrough wherein the work is removed from the furnace by contact with a supporting member having an inclined plane. An example of such a furnace is a walking beam furnace wherein the end portion of the stationary rails of the walking beam furnace is inclined downwardly and a vertically moving member is provided which contacts the work and causes it to move down the incline through the force of gravity.

4 Claims, 3 Drawing Figures PATENTEDsme m2 SHEET 1 BF 2 Ill m cw

M T a 2 r r 8 A DISCHARGE MECHANISM FOR A WALKING BEAM FURNACE This invention relates to means for conveying work through furnaces such as walking beam and pusher types and, more particularly, to means for discharging work from such furnaces. In the heat treating of metal billets, slabs, plates, and the like, a problem is presented in removing the work from the furnace after the completion of the heat treat operation. It is desirable that the work be removed quickly in order to eliminate dwell time over the discharge ramp, thereby reducing thermal differentials in the slabs and avoiding impact. An example of such furnaces is a walking beam furnace. The instant invention will be described by application to a walking beam furnace, but it will be understood that the principles involved may be applied to other types of furnaces as well.

Present walking beam furnaces require the walking beam member act as a means for moving the last slab the slab passes the slope knuckle on those furnaces providing an inclined discharge ramp. In addition, the impact on the work and work support members is rather high with this type of discharge mechanism. It is possible to provide pull-out or lift-off mechanisms to remove the work when it reaches a given location; however, these mechanisms would be complicated and expensive.

It is, therefore, an object of this invention to provide a novel discharge mechanism for a furnace having means to convey work therethrough.

It is another object of this invention to provide a discharge mechanism for a furnace which is able to remove the work from the furnace quickly. I 7

It is still another object of this invention to provide a discharge mechanism for a furnace wherein impact upon the work and upon the work support members is eliminated.

It is a further object of this invention to provide a relatively simple and inexpensive discharge mechanism for a walking beam furnace.

These and other objects are achieved by the mechanism described and shown in the instant specification and accompanying drawing wherein:

FIG. I is a longitudinal cross sectional view of a walking beam furnace embodying the concepts of this invention. I

FIG. 2 is a cross sectional view of the furnace shown in FIG. 1 taken along the lines 2-2.

FIG. 3 is a plan view taken along the lines 33 of FIG. 2.

Referring now to the drawings, a walking beam furnace is shown generally at and has a housing 12 with a charge opening 14 and a discharge opening 16. Adjacent the charge opening 14 is a vertically movable charge door 18, while the discharge opening 16 has a discharge door 20 which pivots about a pin 22. Immediately in front of the charge opening 14 is a charge table 24, and within the housing 12 a flue 26 is provided adjacent the charge opening 14 or upstream end of the furnace l0.

Extending the length of the furnace 10 is a pair of stationary work support members 28, or stationary rails, which rails are held in place by a plurality of frame members 30 which, in turn, are secured to a hearth 32. For purposes of illustration, work 33, in the ble rails, 34. These movable rails 34 are secured to a plurality of stanchions 36 which, in turn, are attached to a carriage 38. The carriage 38 is operatively connected to an eccentric wheel 40 by appropriate means (not shown). The reader is referred to U.S. Pat. No. 3,471,134 for details of the drive mechanism utilizing a concentric wheel wherein work 33 is lifted by the movable rails 34 and moved in increments along the length of the furnace 10. The same does not form part of this invention and the instant invention has utility with a variety of mechanisms for conveying work within the furnace. I

Located above the stationary work support members 28 are a plurality of upper burners 42, and located below the work support members are another plurality of lower burners 44. These burners 42, 44 extend the length of the furnace 10. The downstream end of the stationary rails 28 has a downwardly sloping portion 46 which passes through the discharge opening 16. The movable rails 34 terminate at a location upstream from the sloping portion 46. Adjacent the sloping portion 46 is a generally horizontal receiving member 48 upon which the work slides to a halt.

In the vicinity of the downstream end of the movable rails 34 is a discharge mechanism 50 having a pair of downwardly sloping rails 52 which assume an angle substantially the same as the angle of the sloping por- .tion 46, which sloping rails 52 are connected to one another by lateral members 54. Support posts 56 are attached to each of the connecting members 54 and are located within a frame member 58 having roller bearing assemblies 59 which receive the support posts. The discharge mechanism 50 is provided with a motor 60, having variable control means 61 (shown schematically), and a gear reducer 62. Upon the output shaft 63 of the gear reducer 62 is a sprocket 64 which engages a belt 66, the other end of the belt 66 being disposed about another sprocket 68. A common shaft 70 supports the sprocket 68 and a second sprocket 72. A chain 74 is disposed about sprocket 72 and a driven sprocket 76. One end of the chain 74 is anchored as by an assembly 78 to the lower portion of one of the su port posts 56. Another sprocket 80 is provided to take up the slack in the chain as it is moved about sprockets 72 and 76.

In operation, the work 33 is conveyed along the lengthof the furnace 10 through the lifting of the work 30 by the movable rails 34, thereby moving the work in increments along the length of the stationary rails 28 until it reaches the end of the horizontal portion of the stationary rails. During initial operation, the discharge mechanism 50 is in its lowermost position, as shown on the left side of FIG. 2. When work 33 reaches the downstream end of the furnace, motor 60 is actuated so that chain 74 rotates about sprocket 76 thereby causing support rods 56 to be raised and the sloping rail 52 to come into contact with the work. When the rail is in its uppermost position it will be generally parallel to the sloping portion 46 and the work 33 will then slide along the rails 46, 52 outwardly through the opening 16 and come to rest on the horizontal receiving member 48.

The length of the sloping rail 52 should be sufficiently large so that it exceeds the longitudinaldimensions of the work 33 being supported thereon, thereby avoiding difficulties with regard to center of gravity of the work 33. As illustrated, the walking portion of the furnace, i.e., the movable rails 34, does not have to convey the work onto the sloping member 46, with the result that'the work is discharged from the furnace in a very rapid fashion. In addition to this, there is no impact upon the work 33 and the sloping portion 46, as would occur when the work is conveyed in increments and falls onto a sloping surface when its center of gravity extends beyond the horizontal portions of the rails 28. It should also be noted that the discharge mechanism 50 is located within the furnace l and that there is no cooling of the work until it is removed from the furnace.

I claim:

1. In a walking beam furnace having a charge opening and discharge opening at opposite ends thereof, stationary longitudinally extending work support members, longitudinally extending work conveyor walking beam members, and means for providing heat to the furnace, the improvement comprising: the stationary members having a downwardly sloping portion which extends through the discharge opening, vertically movable work support members located within said furnace adjacent the location where the stationary member begins to slope, and means for selectively operating said vertically movable member.

2. The apparatus of claim 1 wherein the angle formed by said vertically movable work support members is substantially equal to the angle formed by said downward sloping portion and the work support surfaces are substantially parallel to one another when said vertically movable member is in its uppermost position.

3. In a walking beam furnace the combination comprising: a longitudinally extending furnace housing having a charge opening and discharge opening at opposite ends thereof, stationary work support members extending longitudinally within said housing and having a downwardly sloping portion which extends through said discharge opening, movable rail means operative to lift work from the stationary support members and move it in increments along the furnace, said movable means terminating before the stationary support members start to slope downwardly, vertically movable work support means located within said housing at the location where the movable rail means terminates and the stationary members slope downwardly, and means for selectively operating said vertically movable member. I

4. The apparatus of claim 3 wherein said vertically movable work support members have an uppersurface that is operative to form a surface substantially parallel to the downwardly sloping portion of the stationary work support members.

P0-1050 Y Y UNITED STATES PATENT OFFICE CLER'fHdQAEE OF CORREC'HGN Patent No. 9 9 0 Dated September 26, 1972 Inventods) Albert T. Enk

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown' below:

Column 2, line 4, delete "Displaced" and substitute therefor Disposed Signed and sealed this 13th day of February 1973.

(SEAL) Attest:

EDWARD M.PLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 

1. In a walking beam furnace having a charge opening and discharge opening at opposite ends thereof, stationary longitudinally extending work support members, longitudinally extending work conveyor walking beam members, and means for providing heat to the furnace, the improvement comprising: the stationary members having a downwardly sloping portion which extends through the discharge opening, vertically movable work support members located within said furnace adjacent the location where the stationary member begins to slope, and means for selectively operating said vertically movable member.
 2. The apparatus of claim 1 wherein the angle formed by said vertically movable work support members is substantially equal to the angle formed by said downward sloping portion and the work support surfaces are substantially parallel to one another when said vertically movable member is in its uppermost position.
 3. In a walking beam furnace the combination comprising: a longitudinally extending furnace housing having a charge opening and discharge opening at opposite ends thereof, stationary work support members extending longitudinally within said housing and having a downwardly sloping portion which extends through said discharge opening, movable rail means operative to lift work from the stationary support members and move it in increments along the furnace, said movable means terminating before the stationary support members start to slope downwardly, vertically movable work support means located within said housing at the location where the movable rail means terminates and the stationary members slope downwardly, and means for selectively operating said vertically movable member.
 4. The apparatus of claim 3 wherein said vertically movable work support members have an upper surface that is operative to form a surface substantially parallel to the downwardly sloping portion of the stationary work support members. 